Question about Devolo dLAN 1200+ WiFi ac extension

For me, a combination of my 1200+ Wifi works with all white devolo adapters (I have different "ages" i use).
It does not work with the old blue devices

ja, problemlos

I would check directly with Devolo, but in my opinion it is possible. However, it is possible that all powerline adapters will then only communicate at a maximum of 200 Mbps. This is not a "switched" network, so the speed will probably be adapted to the slowest device.